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Volkswagon - 300 mi in 15 min...

So, looks like VW is trying to make up for their ridiculous diesel issues with the EV push. Saw this article today that VW is looking to bring out a 300+ mi range car in late 2018/early 2019. That's great, but the thing that I can't see really being realistic is the 15 minute charge time.

With Tesla currently just scraping by being able to provide Supercharging for its fleet, where on Earth are these VW chargers going to be that can pump that insanely high amount of electricity to a car? I'd think that home installs would be on a whole other level of expense and don't think that unless VW directly invests in putting them in that you'd ever see one put in by a city.

An insanely big of expensive battery might take so much charge. Think of hybid race car batteries. Those are bulky, though.
As with Porsche, it's cool if you have a nuclear powerstation on every corner on the street. Promising faster than Tesla's charging does little more than seed hope that people will buy a petrol car, today. I'd be pleasantly surprised if the Germans actually put their heads (wallets) together to build equivalent overnight ultracharging infrastructure, even in their home market.

Unless the Germans have come up with a cost-effective battery sytem that can both carry a lot of energy, but also charge really quickly, I suspect they are stuck with copying Tesla/Nissan and spending way more per kWh.

That's 300 miles NEDC...so certainly doable. The 15 min charge is less than likely, however.

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It's possible if they do go with the 800V architecture. Currently Tesla gets about 200 miles NEDC in a 30 minute charge (with 120kW peak). Direct scaling says they need a 360kW speed to get 300 miles NEDC in 15 minutes.

I didn't know about CSS. Seems they want to take it to a whole new level before they tip their toes.
For Tesla I hope their SC's can be updated without too much cost/effort to keep additional locations for their customers.
The last few days I've been thinking, that soon the closest decent charger will be closer than the nearest gas station. Easier one-time infra investment, not daily petrol trucks to supply a station.

Best wishes for Volkswagen to achieve their stated goals of 300 mile range and 15 minute charging.
Now just bring the new EV products matching those specifications to market.
(Same message for Porsche.)

The more viable full EVs on the road from multiple manufacturer's the better.
Once they decide to get into the EV market and make vehicles available to all VW dealers and install their charging system network, better for the consumers to make well-informed buying decisions.

Making compliance cars in limited states has been a half-hearted effort.
I have yet to see an factory-made electric VW Golf.
(There is a local owner who converted his Golf to be an EV.)
If it is a great car, bring it to Texas and sell it here.
And in the rest of the U.S. too.

Either get with the program and commit to excellence, or shut up.
Talking about something is NOT the same thing as accomplishing it and bringing it to full public market.

It's possible if they do go with the 800V architecture. Currently Tesla gets about 200 miles NEDC in a 30 minute charge (with 120kW peak). Direct scaling says they need a 360kW speed to get 300 miles NEDC in 15 minutes.

The future CCS spec is expected to top out around 350A for continuous charging which is about the same as today's Supercharger current. The trick is in doubling the voltage from today's nominal peak of 500V to 1000V. Realistically, that means more like 800V or roughly twice what a Model S 90-100 charges at. So, the peak future CCS charging rate is realistically more like 240 kW or twice today's Supercharger rate. Today's high energy density batteries will have a hard time keeping up with a rate that fast.

The future CCS spec is expected to top out around 350A for continuous charging which is about the same as today's Supercharger current. The trick is in doubling the voltage from today's nominal peak of 500V to 1000V. Realistically, that means more like 800V or roughly twice what a Model S 90-100 charges at. So, the peak future CCS charging rate is realistically more like 240 kW or twice today's Supercharger rate. Today's high energy density batteries will have a hard time keeping up with a rate that fast.

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Good point about the current limits. The figure I use for Tesla is a real world average given a 120kW peak (200 miles NEDC in 30 minutes is not at a continuous 120kW), so the peak numbers matter more. I believe the highest current observed is 370A.

The battery is going to be a challenge, but I believe it will either be addressed by a power optimized pack or by increasing capacity.

The quickest NMC based pack is for the Kia Soul EV. It can charge at 70kW for a 30.5kWh pack or 2.3C. NMC is what most non-Tesla automakers will be using (LTO based packs are faster but has poor energy density). 240kW would mean a 104kWh pack and 320kW would mean 139kWh. VW will probably tweak it a bit more (maybe like 3C +), so they can get to the 300+kW with a ~100kWh pack (according to their announced goals).https://www.linkedin.com/pulse/opens-120-kw-ev-charger-public-leif-richard-bones-egge

For Tesla, the pathway to doubling the power would be with higher capacity. Highest observed peak rate is 1.75C (105kW/60kWh), so 240kW means a 137kWh pack, and 320kW a 183kWh pack.

The quickest NMC based pack is for the Kia Soul EV. It can charge at 70kW for a 30.5kWh pack or 2.3C.

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The 2014 Spark has a 21 kWh pack using cells from A123 but the 2015 Spark uses cells from LG. I believe the Spark LG pack has been observed charging at up to 48 kW. That pack has often been reported as being 19 kWh but GM docs show it to be 18.4 kWh with the same number of cells as the 18.4 kWh pack in the 2016-2017 Volt and the cells are roughly the same size. Thus, I'm assuming it uses the same somewhat power-oriented NMC/LMO cells as the Volt.

The 2014 Spark has a 21 kWh pack using cells from A123 but the 2015 Spark uses cells from LG. I believe the Spark LG pack has been observed charging at up to 48 kW. That pack has often been reported as being 19 kWh but GM docs show it to be 18.4 kWh with the same number of cells as the 18.4 kWh pack in the 2016-2017 Volt and the cells are roughly the same size. Thus, I'm assuming it uses the same somewhat power-oriented NMC/LMO cells as the Volt.

So, that would be 48 kW / 18.4 kWh or about 2.6 C.

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I was thinking of doing the Spark as an example (I remember it being one of the quickest also), but there is some ambiguity about the capacity / lack of sources for charging speed. Plus it's a NMC/LMO mix as you mention (mainly LMO with a sprinkling of NMC for better density) and not the "full" NMC that the Soul uses (and other planned EVs will be using). However, I imagine VW (and others) will be doing some similar mixes to tweak the balance between power and density.

I also wonder how practical it is to change the entire high voltage system to 800VDC. Can standard IGBT's used in today's traction inverters handle that? The other way to do it would be to have the pack divided in half and use contactors to allow one half or the other or the pair in series to be DC charged, then put back in parallel for vehicle use. It did occur to me that there would be a problem making sure they are exactly the same voltage before putting them back in parallel. That's why you would have to allow charging one half or the other separately to balance them. Either that or the car would just use the higher charged half until they are balanced and then put them back in parallel.

FYI I was a former Audi owner and I LOVED my A3 Quattro. But after having critical maintenance problems and Audi refusing to reimburse me for parts, I lost all trust and respect for VW. The last straw was dieselgate. I can't understand how anyone continues to support them after that scandal.

I will never by a car from VW or its sub-brands ever again. Dislike all you want.

I also wonder how practical it is to change the entire high voltage system to 800VDC. Can standard IGBT's used in today's traction inverters handle that?

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I don't know much about inverter design but the Prius and two-motor Honda hybrids run their motors at 650-700V for efficiency. They have battery packs with under 300 volts but use a DC-DC conversion circuit to bump the voltage.

On the other hand, they might just configure the battery for charging at 800V only when plugged in at chargers that support that but then run the rest of the time at 400V and reuse all of the existing motors and inverters.

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